Re-open the checker application, choose again, but select the core operational software payload file named appli.com . Click Download the Flash App once more to finalize the memory update. Troubleshooting Common Diagnostic Faults
Antivirus programs often flag the interface checker or Diagbox components as false positives. Disable them before running the tool.
For owners, enthusiasts, and mechanics working on Peugeot, Citroën, DS, or Opel vehicles, the diagnostic setup relies heavily on the multiplexer hardware running PSA Diagbox software . However, operating a cloned or aftermarket interface often brings specific challenges—such as the dreaded "Init KO" error, a failure to identify the VIN, or sudden communication blackouts with specific vehicle Electronic Control Units (ECUs).
: Connect the VCI to a PC via USB (vehicle connection is not usually required for firmware checking). Activation : Run the checker tool and select "Activate" to establish communication with the hardware. Check Version to see the currently installed firmware. Reference Link psa interface checker 440 link
PSA introduced a rolling code handshake around 2012. Clone interfaces cannot emulate this perfectly. The solution:
: Flashing a Revision B unit to Revision C via software will not fix communication issues if the physical hardware (chips) is missing.
The market is flooded with cheap Lexia 3 "full chip" interfaces from eBay or Amazon. Many of these clones have poor soldering on the CAN transceiver chip. A weak solder joint on pin 6 or 14 of the OBD connector is the #1 cause of a dead 440 link. Re-open the checker application, choose again, but select
The PSA Interface Checker tool is generally bundled within the Diagbox installation package (usually found in C:\AWRoot\bin\fi\ . However, you can download a standalone version if needed.
Set your multimeter to DC Volts.
Plug your Lexia 3 VCI into a high-quality USB 2.0 port on your computer. Disable them before running the tool
of your VCI (Vehicle Communication Interface). This is especially important for users with "clone" devices, where manual intervention is sometimes needed to keep the device compatible with different versions of Key Features of the Tool
: Technicians use it to determine if a device is a Revision B or Revision C . Revision C is generally required for compatibility with newer versions of Diagbox (v7.xx and higher) and for full communication with modern CAN-bus vehicles.
: If you experience communication issues (e.g., "ECU not responding"), the Checker helps determine if the issue is a missing hardware component in the interface or a software/driver conflict. Identifying Genuine vs. Clone Hardware Revision Status : High-quality "Full Chip" interfaces will show as Reference 921815C in the Checker. Older or lower-quality clones often show as Revision B
Ensure you are using the most up-to-date version of the 440 link, as updates are required to maintain compatibility with new LIS software revisions. Steps to Perform a PSA Interface Check (440 Procedure)
